Kjeld Aabo

MAN B&W Diesel

© MAN B&W Diesel

NorShipping 2007

Operation on Low Sulphur Fuel and implications for engine Manufacturers / Operators

AgendaDemand to Engine BuildersEngine conditions and performanceIncompatibility of fuelsIgnition and combustion characteristicsChange-over between fuelsFuel viscosityCorrelation between low sulphur fuel cylinder lube oil BN and cylinder lube oil feed rateFuel and cylinder lube oil systemsSummary by Kjeld Aabo

Director Customer Support MAN B&W Diesel A/S

Chairman of CIMAC, Heavy Fuel Working Group2100/KEA/BRO

MAN B&W Diesel

© MAN B&W Diesel

10K98MC-C and 6S35MC on the same Testbed

L/74236-1.0/0402 (3000/OG)

MAN B&W Diesel

© MAN B&W Diesel

Today's Fuel Oils

• Safety

• Optimum engine layout

• High efficiency/low fuel consumption

• Low operation cost (MTBO)

• Reliability/availability

• Exhaust gas emission control

Marked demand to engine builders

L/7534-5.0/1002 (2100/KEA)

MAN B&W Diesel

© MAN B&W Diesel

How to ensure good engine operating condition

Monitoring and inspection

Check of :General performanceCylinder condition

(Turbocharger, cylinder condition, fuel equipment, exhaust gas system)

Overhaul in case of irregularities only

No indication that fuel is the cause of engineoperational problems when the engine condtion is good and the fuel treatment is working properly

[Database ref. and Dept/Ref.…] 2006/09/01

MAN B&W Diesel

© MAN B&W Diesel

External factors which influencesengine condition

Cylinder lube oilQualityType (BN)Dosage

Fuel oilContaminantsCat fines (treatment, purification)

Ambient conditionHumidityWater mist catcher

Exhaust gas boilerPressure drop in exhaust system

MAN B&W Diesel

© MAN B&W Diesel

Low sulphur Fuels seen on the marked today.

Tendency for the low sulphur fuels seen on the marked today

To have lower ignition quality.

Can call for attention in connection with High and Medium speed engines.

To have an increase in cat-fine level.

Calls for even higher attention on operation of fuel centrifuges

Low Viscosity when using DO and GO

New Blends?

2100/KEA/BRO

MAN B&W Diesel

© MAN B&W Diesel

Incompatibility of fuels

Incompatibility of fuels

When switching from HFO to a distillate fuel with low aromatic hydrocarbon there is a risk of incompatibility.

The asphaltenes of the HFO are likely to precipitate as heavy sludge with clogging filters as result.

Use of test compatibility kit on board or guarantee from fuel supplier that fuels used can be blended

2100/KEA/BRO

MAN B&W Diesel

© MAN B&W Diesel

ROHR (Rate of Heat Release) Curve

(2100/KEA)

MAN B&W Diesel

© MAN B&W Diesel

Damage to Fuel Pump Plunger

L/3330187/20030423 (2100/KEA)

MAN B&W Diesel

© MAN B&W Diesel

Low sulphur Fuels operation.

Viscosity

Use of DO and GO when low sulphur HFO is not available.

The ”change over” procedure between fuels with different viscosities.

2100/KEA/BRO

MAN B&W Diesel

© MAN B&W Diesel

Marine Fuels

1

10

100

1000

10000

100000

-15 35 85 135Temperature Degrees Celsius

Kinematic Viscosity

Marine Gas OilMarine Diesel OilIF-30IF-60IF-100IF-180IF-380

MBD limitmin. 2 cst

3332013.2004.11.05 (2100/KEA)

MAN B&W Diesel

© MAN B&W Diesel

Fuel Oil System

3332014.2004.11.05 (2100/KEA)

MAN B&W Diesel

© MAN B&W Diesel

Methods for determination of fuel quality

FIA

Ignition delay

Combustion quality (Rate of Heat Release ROHR)

CCAI / CII

Calculation of fuel ignition quality by use of viscosity and density

MAN B&W Diesel

© MAN B&W Diesel

Ignition delay

Physical ignition delay- Oil moving through the fuel valve- Injection

Chemical ignition delay- Self ignition- Combustion starts

Physical ignition delay is 10 x chemical ignition delay

MAN B&W Diesel

© MAN B&W Diesel

Fuel jet

MAN B&W Diesel

© MAN B&W Diesel

Fuel Acceptance

A: Fuel injection period (~22 deg. crankshaft) ~35 msec for two-stroke

~ 9 msec for four-stroke

B: Possible max ignition delay~20 msec for two-stroke and four-stroke

Low speed (two-stroke)60/103.4 = 0.58 sec/rev

Medium speed (four-stroke)60/600 = 0.10 sec/rev

In medium speed engines all fuel can beinjected before ignition i.e. detonation mayoccur if delay due to fuel quality is large.

1 rev

Sec

Cylinder pressure

L/6254-7.0/0502 (3230/JH)

MAN B&W Diesel

© MAN B&W Diesel

MBD test of different fuels

MAN B&W Diesel

© MAN B&W Diesel

FIA - 100 FCA

Constant volume spray combustion chamber:Tinit = 800K, Pinit = 45bar

Pressure trace Heat release rate

MAN B&W Diesel

© MAN B&W Diesel

Measurement of ignition delayon the 4T50MX test engine

Ignition delay vs. cylinder pressure

5e+06 1e+07 1.5e+07Cyl. pressure at injection (Pa)

0

0.001

0.002

0.003

0.004

0.005

Igni

tion

dela

y (s

ec)

Reference DieselReference HFOSantos fuel

MAN B&W Diesel

© MAN B&W Diesel

Optimising performance in Combustion Chamber

CIMAC, Oslo 25th January 2006 H. Rolsted 2300

MAN B&W Diesel

© MAN B&W Diesel

Optimising the Cylinder Condition Lubrication versus Maintenance

Why lube 2-stroke cylinders?

To clean the moving parts (Ring, grooves and ring lands) from deposits formed by the combustion (detergency)

To transport deposits - dissolved or neutralised by the oil - away from the combustion chamber

To lower the friction and prevent seizures by separating the liner and rings by an oil film. (Lubricate)

To apply additives, to control corrosion

To apply additives, to control corrosion

CIMAC, Oslo 25th January 2006 Henrik Rolsted

MAN B&W Diesel

© MAN B&W Diesel


Liner wear rate as function of lube dosage

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5 1.6lube dosage (g/bhph)

Line

r wea

r (m

m/1

000h

)

0.10 mm/1000h

0.05 mm/1000h

0.02 mm/1000h

High w

ear d

ue to

oil s

tarva

tion

(bou

ndar

y lub

ricati

on)

Normal

Corros

ive w

ear

Scuff

ing w

ear d

ue to

exce

ss

CaCO3

MAN B&W Diesel

© MAN B&W Diesel

Cylinder Condition

Liner polish

MAN B&W Diesel

© MAN B&W Diesel

Cylinder condition

Piston crown with deposits

MAN B&W Diesel

© MAN B&W Diesel

Chemical Conversion of S to H2SO4

SO2

[02]S

Fast100% Conversion

SO3

[0]

Slower0.3 - 7%

Conversion

EquilibriumPressure & Temp.

Dependent

H 2SO4

[H 20]

3332005.2004.11.05 (2100/KEA)

MAN B&W Diesel

© MAN B&W Diesel

Cylinder Liner Surface

L/71509-0.0/0301 (2100/KEA)

MAN B&W Diesel

© MAN B&W Diesel

Experience and Case Stories ofLow-sulphur Fuel Oil Operation

Too little corrosion may result in too little wear and in damaging polishing of the liner surface

A BN 70 can therefore be a less optimal solution than a BN 50 cylinder lube oil

But a BN50 oil will also have to be designed for the purpose

Too High Calcium Carbonate amount =

Chemical bore polish

Mechanical bore polish

L/71525-6.0/0301 (2100/KEA)

MAN B&W Diesel

© MAN B&W Diesel

Experience with Tested Oils

Running-in test.Failed 40BN candidate

Running-in testFailed 40BN candidate

Running-in testPromising candidate

L/71513-6.0/0301 (2100/KEA)

MAN B&W Diesel

© MAN B&W Diesel L/71528-1.0/0301 (2100/KEA)

Low-sulphur Fuel and Low-BN Cylinder Oil - Service Experience

Engine type 4 x 12K90MC-S

Fuel type High viscosity HFO with a sulphur content of 0.2-1.0%

Cylinder oil feed rate Currently at 0.85 g/BHPh

The plant entered operation in November 1998 and suffered from cylinder liner scuffing shortly after starting

After the introduction of a BN 40 oil in August 2000, the liner and ring started to heal themselves and no more scuffing incidents occurred

Case story 3

MAN B&W Diesel

© MAN B&W Diesel 3333011.2005.09.05 (2160/KEA)

Use of BN40 Cylinder oil feed ratesLow S fuel, Alpha ACC

The correlation between fuel sulphur level and cylinder oil can be shown as follows:Fuel sulphur level <1%: BN40/50 recommended Changeover from BN70 to BN40/50 only when operating for more than one week on <1% sulphur Fuel sulphur level 1-1.5%: BN40/50 and BN70 can be used Fuel sulphur level >1.5%: BN70 is recommended

0,000,100,200,300,400,500,600,700,800,901,001,101,201,301,401,501,601,70

0 1 2 3 4 5

Sulphur %

Abs

olut

e do

sage

s (g

/kW

h)

BN70, F x S%, where F = [0.26-0.34]g/kWh

BN40, F

x S%, w

here

F = 70/40

x [0.

26-0.

34] g

/kWh

MAN B&W Diesel

© MAN B&W Diesel


Lubricating oils

Low speed main enginesAuxiliary enginesL23/30 & L28/32

Auxiliary enginesL16/24, L21/31 & L27/38

Type Circulating oil Cylinder oil Circulating oil Circulating oilRequirement SAE30/BN 5-10 SAE50/BN 70-80 SAE50/BN 40-50 SAE30/BN 20-25 SAE40/BN 20-40

Oil company

BP OE-HT 30 CLO-50M CL/CL-DX 405 IC-HFX 203 IC-HFX 204/304/404Castrol CDX 30 Cyltech 70 Cyltech 40SX/40S TLX 203 TLX 204/304/404

Chevron Veritas 800 Marine 30 Delo Cyloil Special Taro Special 50 Delo 2000 Marine 30 Delo 3400 Marine 40Total Atlanta Marine D3005 Talusia HR 70 Talusia LS 40 Aurella 3020 Aurella 4020 – 4030Exxon Exxmar XA Exxmar X70 Mobilgard L540 Exxmar 24 TP30 Exxmar 30 TP40Mobil Mobilgard 300 Mobilgard 570 Mobilgard L540 Mobilgard (TB 25) Mobilgard M430-M440Shell Melina 30/30S Alexia 50 Alexia LS Argina oil S30 Argina oil S40

Texaco Doro AR30 Taro Special HT70 Taro Special 50 Taro 20 DP 30 Taro 20 DP 40, 30 DP 40

CIMAC, Oslo 25th January 2006 Henrik Rolsted

MAN B&W Diesel

© MAN B&W Diesel

One MDO Settling Tank and Two Sets of HFO Settlingand Service Tanks

ServiceTank(day)35°C

ServiceTank(day)90°C

Centrifuge(s)(40°C)

Centrifuge(s)(95 - 100 °C)

ServiceTank(day)90°CCentrifuge(s)

(95 - 100 °C)

HFOSupplypump

HFOCirculating

pump

If unifuel systemTo Gensets

MDO Storage Tank (25°C)

Set

tling T

ank

( 25°

C)

Settl

ing

ank

1(6

0°C

)

Bunker Storage Tank 1 (45°C)



Set

tling

ank

2(6

0°C

)T

T

3332008.2004.11.05 (2100/KEA)

MAN B&W Diesel

© MAN B&W Diesel

Two IndependentCylinder Oil Systems

Cylinder OilStorage Tank 1

Cylinder OilService Tank 1

Cylinder OilStorage Tank 2

Cylinder OilService Tank 2

3m

3332011.2004.11.05 (2100/KEA)

MAN B&W Diesel

© MAN B&W Diesel

Low Sulphur Heavy Fuel Operation

Summary

Exhaust gas from marine engines will be further regulated and new fuels

will be utilised in the marine industry.

1. Demands to Engine condition and Fuel cleaning systems also for future fuels.

2. No difference in performance of engines between low sulphur fuel, DO/GO and HFO.

3. However, necessary precautions have to be taken by operators.

4. Marine Industry has to follow carefully the development of low sulphur fuel oils to ensure proper quality.

2100/KEA/BRO

MAN B&W Diesel

© MAN B&W Diesel

Legislation

LegislationIMO (International Convention)

Annex VI regulations for ”Prevention of Air Pollutions from ships”EU (Local Area)

Directive 99/32EC includes combustion of diesel and HFO by shipsand a desire to limit sulphur oxide emissionsCAFÉ study may incorporate measures to reduce emissions from ships – P.M. NOx & SOx

USA (Local Area)EPA – step 1 as IMO step 2 from 2007 more restrictive.CARB – faced with local air quality excursions

Other AuthoritiesAlaska – opacity requirements monitored

2100/KEA/BRO

MAN B&W Diesel

© MAN B&W Diesel

Emission Status

Emission of particulates as a function of fuel sulphur content

PM – emission %100

90

80

70

60

50

40

30

20

10

00.2 0.8 1.4 2.0Comments:

Measuring method: EPA 17 Fuel-S %

L/71317-2.0/1100 (3230/JH)

Kjeld Aabo

Documents

Transcript of Kjeld Aabo